1. Field of the Invention
The present invention relates to a condensate discharge device for automatically discharging a condensate generated in equipment using steam, a steam piping system used in steam handling equipment, or in a steam pipeline, and in particular for to an apparatus preventing metal ions dissolved in fluid from accumulating on a condensate discharge port surface of a discharge passage and thereby blocking up the condensate discharge port.
2. Description of the Prior Art
In a steam piping system, the generation of condensate is unavoidable, and it is necessary to discharge the condensate out of the system in some manner. A device for automatically discharging the condensate from a steam piping system is a special valve called a steam trap.
A steam trap may be classified into three categories: a mechanical type, driven on the basis of the principle of a valve member and utilizing the difference in specific gravity between steam and condensate; a thermodynamic type, utilizing the difference in thermodynamic characteristics between the steam and the condensate; and a thermostatic type, utilizing the difference in temperature between the steam and the condensate. According to the basic constitution of such steam traps, an inlet, a valve chamber, and an outlet are formed in a valve casing; a condensate discharge port is formed, connecting the valve chamber and the outlet to the valve casing or to a valve seat member mounted to the valve casing; and the valve member is disposed within the valve chamber so that the condensate flowing from the upstream pipe--connected with the inlet by the valve member opening and closing the condensate discharge port--is automatically discharged to the outlet. The material of the valve casing is generally a ferrous metal, such as cast iron, cast steel, etc.; the valve seat member forming the condensate discharge port is generally formed of a stainless steel with abrasion-resistance taken into consideration. When the valve port formed in the valve casing or when the valve casing is small, the valve casing is generally made of a stainless steel.
EPO Patent Application No. 0 016 241 shows a device for removing condensate from steam lines, steam systems, and other systems wherein a liquid must be removed. The device in that patent application includes an orifice which allows the removal of liquids through the orifice but not the escape of steam or gas through the orifice.